Difference between revisions of "MPU Battery Replacement Options"
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=Introduction= | =Introduction= | ||
− | RAM chips are typically used to store game settings and | + | RAM chips are typically used to store game settings and bookkeeping data. However, RAM is volatile and can only store data if power is applied to the chip. If power is lost, so is the data. So, the solution to this was to include a battery on the MPU to retain the data in RAM when the game was turned off. |
Unfortunately, many of these batteries leak and damage or destroy circuit boards in the process. So, it is imperative that the battery is removed from the MPU in order to prevent this damage in the future. | Unfortunately, many of these batteries leak and damage or destroy circuit boards in the process. So, it is imperative that the battery is removed from the MPU in order to prevent this damage in the future. | ||
− | In order to retain the data for game settings and | + | In order to retain the data for game settings and bookkeeping, there are a few different options to replace the original battery and prevent future problems from leakage. |
+ | This guide assumes that the old battery has already been removed from the MPU and any damaged caused by a leaking battery has been cleaned up and repaired. | ||
==Remote Battery Pack== | ==Remote Battery Pack== | ||
− | The remote battery solution is when a battery pack is installed in a game, but lead wires are attached to the positive and negative solder points on the MPU. The safest place to mount a remote battery pack is below any circuit boards and as far away from them as possible, so as to avoid escaping gas and drippings from leaks. | + | The remote battery solution is when a battery pack is installed in a game, but lead wires are attached to the positive and negative solder points on the MPU. |
+ | |||
+ | [[File:Leaked batteries.jpg|left|thumb|200px|Battery pack installed on a Gottlieb Genesis. User failed to install a blocking diode. Pic courtesy of Ray Brackins at Wide Area Repair]]<br> | ||
+ | On older game systems that originally had a rechargeable battery installed, a diode must also be installed to prevent the MPU from attempting to charge the non-rechargeable batteries (referred to as a "blocking diode"), otherwise the batteries may expand, leak, and/or explode. | ||
+ | <br clear=all> | ||
+ | |||
+ | The safest place to mount a remote battery pack is below any circuit boards and as far away from them as possible, so as to avoid escaping gas and drippings from leaks. It has been reported that circuit boards have been affected by the gas from leaking batteries as far as 6 inches away. | ||
+ | |||
+ | Additionally, it can be a good idea to put the battery pack inside a zip lock bag to help limit damage from a leaking battery. | ||
==Lithium Battery== | ==Lithium Battery== | ||
Line 17: | Line 27: | ||
Installing batteries directly onto the MPU leaves the game open to the possibility of an owner replacing a dead AA lithium battery with a AA alkaline battery if they don't have a lithium battery on-hand because it's the easy and lazy thing to do. As a result, battery leakage becomes a serious risk again. | Installing batteries directly onto the MPU leaves the game open to the possibility of an owner replacing a dead AA lithium battery with a AA alkaline battery if they don't have a lithium battery on-hand because it's the easy and lazy thing to do. As a result, battery leakage becomes a serious risk again. | ||
+ | ==Memory Capacitor== | ||
+ | Memory capacitors are special capacitors that hold a charge for an extended period of time and take the place of a battery. The downside is that the game has to be turned on at least once for several hours every 14-30 days in order to build up to a full charge. However, there are reported instances where a memory capacitor has held for over a year on a Gottlieb System 80B MPU. | ||
− | + | Note that on some game systems, a resistor with a higher resistance and/or wattage must be installed in order to handle the inrush of current, especially since a depleted memory capacitor can briefly act as a dead short. | |
− | + | ||
+ | Note that on games systems with a real-time clock, a memory capacitor will only last a few days, since energy is being drained by both the clock and the RAM. | ||
− | Additionally, lower quality capacitors are prone to leaking, though not as spectacularly as alkaline or NiCad batteries. | + | Additionally, lower quality capacitors are prone to leaking, though not as spectacularly as alkaline or NiCad batteries, so it is important to stick with a reputable brand. |
− | + | Memory capacitors have fallen from favor for some people, because of only holding a short-term charge, as well as the introduction and economical prices of lithium batteries, lithium coin cell batteries, and NVRAM. | |
+ | Systems which are best fit to use a memory capacitor are Gottlieb System 80/ 80A /80B, Bally -17 / -35 / 6803, and Stern M-100 and M-200. Data East MPUs fare pretty well too, however, Williams System 11 and its variants for some reason do not. | ||
==Coin Cell / Button Battery== | ==Coin Cell / Button Battery== | ||
− | Lithium coin cell batteries (also known as button batteries) are much less prone to leakage than the batteries originally used on MPUs. They typically have a 10-year life span when used on an MPU. Gottlieb System 3 MPUs were the first to utilize coin cell batteries. | + | Lithium coin cell batteries (also known as button batteries) are much less prone to leakage than the batteries originally used on MPUs. They typically have about a 10-year life span when used on an MPU. Gottlieb System 3 MPUs were the first to utilize coin cell batteries. |
+ | |||
+ | On older game systems that originally had a rechargeable battery installed, a diode must also be installed to prevent the MPU from attempting to charge the non-rechargeable lithium battery (referred to as a "blocking diode"), otherwise the battery may expand, leak, and/or explode. | ||
+ | |||
+ | Note that through normal usage, the risk of a lithium battery leaking is pretty small, but they still can--and do--leak after enough time. Poor storage conditions are also sometimes a contributing factor. | ||
+ | [[file:gtb-sys3-mpu-battery-leak.jpg|thumb|left|250px|Gottlieb System 3 MPU with a leaking coin cell battery]]<br clear=all> | ||
==NVRAM== | ==NVRAM== | ||
Line 35: | Line 54: | ||
Various game systems use different types of RAM, so adapters are needed to adapt the footprint and pinout of the 6264 NVRAM pinout to the RAM footprint/socket that the game system is using. | Various game systems use different types of RAM, so adapters are needed to adapt the footprint and pinout of the 6264 NVRAM pinout to the RAM footprint/socket that the game system is using. | ||
− | NVRAM adapters typically list which RAM | + | NVRAM adapters typically list which RAM footprints/sockets and/or game systems they are intended to support. |
===Products=== | ===Products=== | ||
− | * [http://lockwhenlit.com/anyPin.htm AnyPin Adapter] | + | Most NVRAM developers sell directly on their websites, but some are also available from various pinball suppliers. |
− | * [http://www.pinitech.com/products/ | + | |
− | * [http://nvram.weebly.com/ Pinball Electronics Adapters] | + | * [http://lockwhenlit.com/anyPin.htm AnyPin Adapter] ([https://www.pinballlife.com/search.html?Search=nvram Pinball Life]) |
− | * [ | + | * [http://www.pinitech.com/products/cat_memory.php Pinitech Adapters] |
+ | * [http://nvram.weebly.com/ Pinball Electronics Adapters (barakandl)] | ||
+ | * [https://pinballelectronics.com/ Pinball Electronics] | ||
=Game Systems= | =Game Systems= | ||
Line 49: | Line 70: | ||
Game data is not saved. A battery solution is not necessary. | Game data is not saved. A battery solution is not necessary. | ||
− | ===Generation 2 | + | ===Generation 2=== |
− | |||
==Alvin G== | ==Alvin G== | ||
Line 60: | Line 80: | ||
===Generation 2=== | ===Generation 2=== | ||
+ | * Remote battery | ||
+ | * Coin cell battery | ||
+ | * [[Atari_Repair#MPU_Issues|Memory capacitor]] | ||
+ | Note: Generation 2 games generally suffer no ill effects when running without a battery, other than that high scores and bookkeeping data would not be retained. | ||
==Bally== | ==Bally== | ||
Line 69: | Line 93: | ||
* Coin Cell Battery | * Coin Cell Battery | ||
* NVRAM | * NVRAM | ||
+ | |||
+ | Note: running some classic Bally games without a battery or battery replacement will cause the game to play default sounds, and not the correct sounds for the game. This affects games like Xenon, Eight Ball Deluxe, Flash Gordon, Skateball, Centaur, Cybernaut, and Fathom. | ||
===6803 MPU=== | ===6803 MPU=== | ||
* [[Bally_6803#Relocating_the_Factory_NiCad_Battery_off_the_MPU|Remote Battery]] | * [[Bally_6803#Relocating_the_Factory_NiCad_Battery_off_the_MPU|Remote Battery]] | ||
+ | * NVRAM | ||
==Capcom== | ==Capcom== | ||
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* [[Data_East/Sega#Relocating_the_Battery_from_the_MPU_board|Remote Battery]] | * [[Data_East/Sega#Relocating_the_Battery_from_the_MPU_board|Remote Battery]] | ||
* [[Data_East/Sega#Installing_a_Memory_Capacitor_Instead_of_Batteries|Memory Capacitor]] | * [[Data_East/Sega#Installing_a_Memory_Capacitor_Instead_of_Batteries|Memory Capacitor]] | ||
− | * Coin Cell Battery | + | * [[Data_East/Sega#Installing_a_Lithium_.22Button_Cell.22_Battery|Coin Cell Battery]] |
* NVRAM | * NVRAM | ||
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===System 1=== | ===System 1=== | ||
* [[Gottlieb_System_1#Relocating_the_Battery_from_the_CPU_board|Remote Battery]] | * [[Gottlieb_System_1#Relocating_the_Battery_from_the_CPU_board|Remote Battery]] | ||
− | * Coin Cell Battery | + | * [[Gottlieb_System_1#Installing_a_Coin_Cell_Battery|Coin Cell Battery]] |
+ | * [http://www.pinitech.com/products/gottlieb_sys1_nvram.php NVRAM] | ||
− | + | Note: Running without a battery attached can sometimes introduce garbage data for the high scores and bookeeping data at power up. | |
===System 80/80A/80B=== | ===System 80/80A/80B=== | ||
Line 102: | Line 130: | ||
===System 3=== | ===System 3=== | ||
* [[Gottlieb_System_3#Relocating_the_battery_from_the_MPU_board|Remote Battery]] | * [[Gottlieb_System_3#Relocating_the_battery_from_the_MPU_board|Remote Battery]] | ||
− | * Coin Cell Battery | + | * [http://www.pinrepair.com/sys3/#battery Coin Cell Battery] |
+ | * [[Gottlieb_System_3#NVRAM_Installation|NVRAM]] | ||
+ | |||
+ | [[File:GottliebSystem3NVRAM.jpg|left|thumb|200px|NVRAM installed with jumpers pictured on a Gottlieb System 3 MPU]]<br clear=all> | ||
+ | |||
+ | Some experimentation leading to the development of an NVRAM solution can be found [https://pinside.com/pinball/forum/topic/nvram-gottlieb-system-3-success here]. | ||
+ | |||
+ | Note: Operating the game with no battery or a failing battery will display the message "low battery or bad U3 or U6". To bypass this error message, press the reset button (SW1) on the MPU. | ||
==Heighway Pinball== | ==Heighway Pinball== | ||
Line 108: | Line 143: | ||
==Jersey Jack Pinball== | ==Jersey Jack Pinball== | ||
− | + | * A coin cell battery is [http://www.ipdb.org/showpic.pl?id=5800&picno=63749&zoom=1 installed on the motherboard]. | |
− | |||
==Sega== | ==Sega== | ||
* [[Sega/Stern_White_Star_Repair#Relocating_the_Battery_from_the_MPU_board|Remote Battery]] | * [[Sega/Stern_White_Star_Repair#Relocating_the_Battery_from_the_MPU_board|Remote Battery]] | ||
* Coin Cell Battery | * Coin Cell Battery | ||
+ | * [[Sega/Stern_White_Star_Repair#Installing_a_Memory_Capacitor_Instead_of_Batteries|Memory capacitor]] | ||
* NVRAM | * NVRAM | ||
Line 126: | Line 161: | ||
* Coin Cell Battery | * Coin Cell Battery | ||
* NVRAM | * NVRAM | ||
+ | |||
+ | Note: The MPU-200 uses two RAM chips and has two RAM sockets. Two separate 5101 adapters can be used, or an adapter that specifically accommodates this board can be used. | ||
+ | |||
+ | Note: When using NVRAM with [[Meteor]]'s production game ROMs, [https://pinside.com/pinball/forum/topic/price-check-1980-sterns-quicksilver-stargazer-seawitch/page/114#post-6486584 there is a sound bug] in that version. An [[Media:Meteora2(1).zip|unofficial updated bug fix ROM]] (by slochar) is available, which clears the sound registers on boot-up before game initialization. | ||
===Whitestar=== | ===Whitestar=== | ||
* [[Sega/Stern_White_Star_Repair#Relocating_the_Battery_from_the_MPU_board|Remote Battery]] | * [[Sega/Stern_White_Star_Repair#Relocating_the_Battery_from_the_MPU_board|Remote Battery]] | ||
* Coin Cell Battery | * Coin Cell Battery | ||
+ | * [[Sega/Stern_White_Star_Repair#Installing_a_Memory_Capacitor_Instead_of_Batteries|Memory capacitor]] | ||
* NVRAM | * NVRAM | ||
Line 138: | Line 178: | ||
===SPIKE=== | ===SPIKE=== | ||
− | + | * A coin cell battery is mounted vertically on the PCB in the backbox. | |
==Williams== | ==Williams== | ||
Line 144: | Line 184: | ||
===System 3-7=== | ===System 3-7=== | ||
* [[Williams_System_3_-_7#Relocating_the_batteries_away_from_the_MPU_board|Remote Battery]] | * [[Williams_System_3_-_7#Relocating_the_batteries_away_from_the_MPU_board|Remote Battery]] | ||
− | * [[Williams_System_3_-_7#Installing_a_Memory_Capacitor_Instead_of_Batteries|Memory Capacitor]] | + | * [[Williams_System_3_-_7#Installing_a_Memory_Capacitor_Instead_of_Batteries|Memory Capacitor]]. [http://tuukan.fliput.net/goldcap_en.html Alternate guide]. |
* Coin Cell Battery | * Coin Cell Battery | ||
− | * NVRAM | + | * [[Williams_System_3_-_7#Installing_NVRAM_Instead_of_Batteries|NVRAM]] |
===System 9=== | ===System 9=== | ||
Line 164: | Line 204: | ||
* [[Williams_WPC#Installing_an_external_battery_on_a_WPC-95_CPU_using_the_Auxiliary_Battery_header_.28J213.29|Remote Battery on WPC-95]] | * [[Williams_WPC#Installing_an_external_battery_on_a_WPC-95_CPU_using_the_Auxiliary_Battery_header_.28J213.29|Remote Battery on WPC-95]] | ||
* Coin Cell Battery | * Coin Cell Battery | ||
− | * NVRAM | + | * [[Williams_WPC#Replacing_the_CPU_RAM_with_non-volatile_RAM|NVRAM]] |
Note: Games that utilize a real-time clock will need a battery instead of NVRAM to keep proper time. Otherwise, the date/time will not advance while the game is powered off. | Note: Games that utilize a real-time clock will need a battery instead of NVRAM to keep proper time. Otherwise, the date/time will not advance while the game is powered off. | ||
Line 185: | Line 225: | ||
* NBA Fastbreak (midnight madness) | * NBA Fastbreak (midnight madness) | ||
* Medieval Madness (midnight madness, but special mode needs to be enabled to activate it) | * Medieval Madness (midnight madness, but special mode needs to be enabled to activate it) | ||
+ | |||
+ | |||
+ | Note that on games systems with a real-time clock, a memory capacitor will keep the clock going, but since energy will be drained by both the RAM and the clock, a fully charged memory capacitor is reported to be able to keep the clock active for about 2-4 days, while the RAM will lose its settings after about 10 days. Additionally, on WPC systems, a minimum of 3v is required to keep the real-time clock alive, while the RAM can sometimes be kept alive until the memory capacitor has drained to as low as 2v with 6264 RAM and 1v with 5101 RAM. | ||
===Pin2000=== | ===Pin2000=== |
Latest revision as of 01:17, 8 June 2022
Note: This page is a work in progress. Please help get it to a completed state by adding any useful information to it. |
1 Introduction
RAM chips are typically used to store game settings and bookkeeping data. However, RAM is volatile and can only store data if power is applied to the chip. If power is lost, so is the data. So, the solution to this was to include a battery on the MPU to retain the data in RAM when the game was turned off.
Unfortunately, many of these batteries leak and damage or destroy circuit boards in the process. So, it is imperative that the battery is removed from the MPU in order to prevent this damage in the future.
In order to retain the data for game settings and bookkeeping, there are a few different options to replace the original battery and prevent future problems from leakage.
This guide assumes that the old battery has already been removed from the MPU and any damaged caused by a leaking battery has been cleaned up and repaired.
1.1 Remote Battery Pack
The remote battery solution is when a battery pack is installed in a game, but lead wires are attached to the positive and negative solder points on the MPU.
On older game systems that originally had a rechargeable battery installed, a diode must also be installed to prevent the MPU from attempting to charge the non-rechargeable batteries (referred to as a "blocking diode"), otherwise the batteries may expand, leak, and/or explode.
The safest place to mount a remote battery pack is below any circuit boards and as far away from them as possible, so as to avoid escaping gas and drippings from leaks. It has been reported that circuit boards have been affected by the gas from leaking batteries as far as 6 inches away.
Additionally, it can be a good idea to put the battery pack inside a zip lock bag to help limit damage from a leaking battery.
1.2 Lithium Battery
Classic Williams games had a build-in battery holder that could fit AA batteries. Unfortunately, it was common to see standard alkaline batteries used in these holders, which always leaked.
Lithium batteries are produced in the AA battery footprint, so can be installed in the battery holders used on classic Williams MPUs. Lithium batteries are less prone to leaking, but it is still a good idea to mount them off the MPU in a remote battery pack.
Installing batteries directly onto the MPU leaves the game open to the possibility of an owner replacing a dead AA lithium battery with a AA alkaline battery if they don't have a lithium battery on-hand because it's the easy and lazy thing to do. As a result, battery leakage becomes a serious risk again.
1.3 Memory Capacitor
Memory capacitors are special capacitors that hold a charge for an extended period of time and take the place of a battery. The downside is that the game has to be turned on at least once for several hours every 14-30 days in order to build up to a full charge. However, there are reported instances where a memory capacitor has held for over a year on a Gottlieb System 80B MPU.
Note that on some game systems, a resistor with a higher resistance and/or wattage must be installed in order to handle the inrush of current, especially since a depleted memory capacitor can briefly act as a dead short.
Note that on games systems with a real-time clock, a memory capacitor will only last a few days, since energy is being drained by both the clock and the RAM.
Additionally, lower quality capacitors are prone to leaking, though not as spectacularly as alkaline or NiCad batteries, so it is important to stick with a reputable brand.
Memory capacitors have fallen from favor for some people, because of only holding a short-term charge, as well as the introduction and economical prices of lithium batteries, lithium coin cell batteries, and NVRAM.
Systems which are best fit to use a memory capacitor are Gottlieb System 80/ 80A /80B, Bally -17 / -35 / 6803, and Stern M-100 and M-200. Data East MPUs fare pretty well too, however, Williams System 11 and its variants for some reason do not.
1.4 Coin Cell / Button Battery
Lithium coin cell batteries (also known as button batteries) are much less prone to leakage than the batteries originally used on MPUs. They typically have about a 10-year life span when used on an MPU. Gottlieb System 3 MPUs were the first to utilize coin cell batteries.
On older game systems that originally had a rechargeable battery installed, a diode must also be installed to prevent the MPU from attempting to charge the non-rechargeable lithium battery (referred to as a "blocking diode"), otherwise the battery may expand, leak, and/or explode.
Note that through normal usage, the risk of a lithium battery leaking is pretty small, but they still can--and do--leak after enough time. Poor storage conditions are also sometimes a contributing factor.
1.5 NVRAM
NVRAM (non-volitile RAM) is being used to replace volatile RAM installed on the MPU. Volatile RAM can only store data if power is applied to the chip. If power is lost, so is the data. NVRAM can retain data without needing any power. It is essentially "frozen" in the chip.
Various game systems use different types of RAM, so adapters are needed to adapt the footprint and pinout of the 6264 NVRAM pinout to the RAM footprint/socket that the game system is using.
NVRAM adapters typically list which RAM footprints/sockets and/or game systems they are intended to support.
1.5.1 Products
Most NVRAM developers sell directly on their websites, but some are also available from various pinball suppliers.
- AnyPin Adapter (Pinball Life)
- Pinitech Adapters
- Pinball Electronics Adapters (barakandl)
- Pinball Electronics
2 Game Systems
2.1 Allied Leisure
2.1.1 Generation 1
Game data is not saved. A battery solution is not necessary.
2.1.2 Generation 2
2.2 Alvin G
- Remote Battery
2.3 Atari
2.3.1 Generation 1
Game data is not saved. A battery solution is not necessary.
2.3.2 Generation 2
- Remote battery
- Coin cell battery
- Memory capacitor
Note: Generation 2 games generally suffer no ill effects when running without a battery, other than that high scores and bookkeeping data would not be retained.
2.4 Bally
2.4.1 -17/-35/-133 MPU
- Remote Battery
- Memory Capacitor
- Coin Cell Battery
- NVRAM
Note: running some classic Bally games without a battery or battery replacement will cause the game to play default sounds, and not the correct sounds for the game. This affects games like Xenon, Eight Ball Deluxe, Flash Gordon, Skateball, Centaur, Cybernaut, and Fathom.
2.4.2 6803 MPU
- Remote Battery
- NVRAM
2.5 Capcom
- NVRAM
2.6 Data East
2.7 GamePlan
- Remote Battery
- NVRAM (not fully tested)
2.8 Gottlieb
2.8.1 System 1
Note: Running without a battery attached can sometimes introduce garbage data for the high scores and bookeeping data at power up.
2.8.2 System 80/80A/80B
- Remote Battery
- Memory Capacitor
- Coin Cell Battery
- NVRAM
2.8.3 System 3
Some experimentation leading to the development of an NVRAM solution can be found here.
Note: Operating the game with no battery or a failing battery will display the message "low battery or bad U3 or U6". To bypass this error message, press the reset button (SW1) on the MPU.
2.9 Heighway Pinball
2.10 Jersey Jack Pinball
- A coin cell battery is installed on the motherboard.
2.11 Sega
- Remote Battery
- Coin Cell Battery
- Memory capacitor
- NVRAM
2.12 Spooky Pinball
2.13 Stern
2.13.1 MPU-100/MPU-200
- Remote Battery
- Memory Capacitor
- Coin Cell Battery
- NVRAM
Note: The MPU-200 uses two RAM chips and has two RAM sockets. Two separate 5101 adapters can be used, or an adapter that specifically accommodates this board can be used.
Note: When using NVRAM with Meteor's production game ROMs, there is a sound bug in that version. An unofficial updated bug fix ROM (by slochar) is available, which clears the sound registers on boot-up before game initialization.
2.13.2 Whitestar
- Remote Battery
- Coin Cell Battery
- Memory capacitor
- NVRAM
2.13.3 SAM
- Remote Battery
- Coin Cell Battery
- NVRAM
2.13.4 SPIKE
- A coin cell battery is mounted vertically on the PCB in the backbox.
2.14 Williams
2.14.1 System 3-7
- Remote Battery
- Memory Capacitor. Alternate guide.
- Coin Cell Battery
- NVRAM
2.14.2 System 9
- Remote Battery
- Memory Capacitor
- Coin Cell Battery
- NVRAM
2.14.3 System 11/11A/11B/11C
- Remote Battery
- Memory Capacitor
- Coin Cell Battery
- NVRAM
2.14.4 WPC
- Remote Battery
- Remote Battery on WPC-95
- Coin Cell Battery
- NVRAM
Note: Games that utilize a real-time clock will need a battery instead of NVRAM to keep proper time. Otherwise, the date/time will not advance while the game is powered off.
2.14.4.1 Games Affected By a Real-Time Clock
WPC (Fliptronics II)
- Creature from the Black Lagoon (different music plays based on the date)
- Twilight Zone (clock on the playfield shows correct time)
WPC-S
- Dirty Harry (midnight madness)
- Johnny Mnemonic (midnight madness)
- WHO dunnit (midnight madness)
- Theatre of Magic ("hermaphrodite position" - midnight madness does not depend on real time clock since it is a game mode)
WPC-95
- Congo (midnight madness)
- Junk Yard (midnight madness)
- NBA Fastbreak (midnight madness)
- Medieval Madness (midnight madness, but special mode needs to be enabled to activate it)
Note that on games systems with a real-time clock, a memory capacitor will keep the clock going, but since energy will be drained by both the RAM and the clock, a fully charged memory capacitor is reported to be able to keep the clock active for about 2-4 days, while the RAM will lose its settings after about 10 days. Additionally, on WPC systems, a minimum of 3v is required to keep the real-time clock alive, while the RAM can sometimes be kept alive until the memory capacitor has drained to as low as 2v with 6264 RAM and 1v with 5101 RAM.